This chapter is from the book

This chapter is from the book

Now it's time to put the UML together with the object-oriented concepts you learned in the last hour. In this hour, you'll firm up your knowledge of object-orientation as you learn more about the UML. You'll learn about

Visualizing a class

Attributes

Operations

Responsibilities and constraints

Discovering classes

Visualizing a Class

As I pointed out in the first hour, a rectangle is the icon that represents
a class in the UML. The name of the class is, by convention, a word with an
initial uppercase letter. It appears near the top of the rectangle. If your
class has a two-word name, join the two words together and capitalize the first
letter of the second word (as in WashingMachine in Figure
3.1).

Another UML construct, the package, can play a role in the name of a class.
As I pointed out in Hour 1, "Introducing the UML," a package is the
UML's way of organizing a diagram's elements. As you might recall, the UML represents
a package as a tabbed folder whose name is a text string (see Figure
3.2).

If the WashingMachine class is part of a package called Household Appliances,
you can give it the name Household appliances::WashingMachine. The double colons
separate the package name on the left from the class name on the right. This
type of class name is called a pathname (see Figure
3.3).